In a wireless communications network, node localization is a very important technology and application, and accurate localization can bring great value.
In the prior art, a location of a to-be-localized node is usually determined by measuring a status of a plurality of radio signals received at a known location. For example, for performing localization based on a fingerprint matching algorithm, first, a status of a plurality of radio signals received at a large quantity of known locations is measured in a to-be-localized area, and for each known location, location information of the known location and a status of a received radio signal are used as a fingerprint and input into a database. Subsequently, matching is performed between a status of a plurality of radio signals received by a to-be-localized node and fingerprints in the database. A fingerprint with a status similar to the status of the radio signals received by the to-be-localized node is selected from the fingerprints in the database. Location information corresponding to the selected fingerprint with the status similar to the status of the radio signals received by the to-be-localized node is used as a location of the to-be-localized node. Localization accuracy of such a node localization manner depends on a size of the fingerprint database. Usually, to increase localization accuracy by twice, the size of the fingerprint database needs to increase by four times or eight times. In addition, a status of the radio signals changes because the radio signals are easily affected by environmental signals. Therefore, the database needs to be updated frequently; otherwise, the localization accuracy greatly decreases.
In conclusion, currently, in a manner of performing localization by using a known-location node, a status of radio signals received at a large quantity of known locations needs to be measured in a case of ensuring localization accuracy, resulting in relatively heavy measurement workload of node localization in the prior art.